Browsing by Author "Kadoli, R."

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A comparison of the non-conforming and conforming sector finite element for free vibration of circular discs
(Elsevier Ltd, 2020) Avvaru, H.T.; Joladarashi, S.; Kadoli, R.
A twelve-term non-conforming and a sixteen-term conforming displacement polynomial are obtained from Pascal's triangle to deduce the shape functions for a sector element. Using the sector element circular disc is discretized. The number of degrees of freedom for the sector element at a given node is three and four. Kirchhoff's plate theory is the basis for strain energy and kinetic energy because of the transverse motion of the circular plate. Associated stiffness and mass matrices for the sector element are derived in closed form using MATHEMATICA. Using the Lagrange equation, the free vibration equation of motion for the circular disc is derived. A validation study is conducted, and non-dimensional frequencies from the finite element solution are compared with the analytical solutions reported in the literature. Subsequently, the natural frequencies of Al-Al2O3functionally graded circular disc with gradation in the thickness direction are evaluated for a variety of boundary conditions. Â© 2020 Elsevier Ltd. All rights reserved.
A multi-unit miniature thermomagnetic generator using half-Heusler (MnNiSi)1?x(Fe2Ge)x alloy for harvesting low-grade waste heat
(Institute of Physics, 2025) Silambarasan, M.; Kadoli, R.; Kondaiah, P.; Deepak, K.
This study focuses on designing and analyzing a series of thermomagnetic generators for efficient low-grade waste heat energy harvesting, addressing the challenge of bulky thermal harvesters that cannot be integrated into small mechanical structures. A miniature harvester with a total height of 16 mm and a diameter of 8 mm was designed. Using a single heat source at a maximum temperature of 450 K, the system drives multiple thermomagnetic generator units connected in series. Each unit utilizes thermomagnetic material with (MnNiSi)1-x(Fe2Ge)x compositions with x values of 0.3, 0.32, 0.33, and 0.34. These materials operate within a Curie temperature range of 300 K to 420 K, enabling continuous operation as the heat transfers between units. Finite element analysis, conducted through COMSOL Multiphysics, was employed for numerical simulation to study the system’s performance. Results show that the three-unit series configuration achieved a peak voltage of 0.2 V per oscillation and 200 oscillations within 60 s. The sequential arrangement of units maximizes residual heat utilization and offers practical applications in industrial waste heat recovery, automotive heat management, and renewable energy systems. © 2025 IOP Publishing Ltd. All rights, including for text and data mining, AI training, and similar technologies, are reserved.
A numerical study on heat transfer characteristics of two-dimensional film cooling
(Pleiades journals, 2019) Ademane, V.G.; Hindasageri, V.; Kadoli, R.
Determination of reference temperature and heat transfer coefficient in case of three temperature problems such as film cooling is one of the fundamental tasks in the design of gas turbines. In the present work, a two-dimensional numerical simulation is carried out for flat surface with 35° angle of injection from slot in case of film cooling problem. The reference temperature, which is represented as film cooling effectiveness, and heat transfer coefficient on the flat surface for different blowing ratio are studied. Heat transfer coefficient obtained from the present simulation is compared with the experimental results from the literature and found to be matching at lower blowing ratios. Turbulence intensity is found to a major contributor in enhancing the heat transfer coefficient. There is an increase in heat transfer with the blowing ratio due to increased turbulence intensity is observed. © Springer Nature Singapore Pte Ltd. 2019.
Adsorption and desorption through packed and fluidized clay-based composite desiccant beds: a comparison study
(Springer Science and Business Media Deutschland GmbH, 2022) Hiremath, C.R.; Kadoli, R.
The present study considers the composite desiccant employing horse dung, sawdust with clay and later impregnating CaCl2 into the host material. The microscopic and spectroscopic experimental methods such as scanning electron microscope (SEM) and X-ray diffraction (XRD) were used to characterize the composite desiccants. The specific heat (Cp) quantification reveals higher values for clay-additives composite desiccants with lower pore volume and larger grain sizes, whereas lower values for clay composite desiccants with higher pore volume and smaller grain sizes. Adsorption–desorption experiments for moisture removal and addition are conducted in a vertical column in static and fluidized states. The desiccant beds are subjected to an initially set value of process air velocity, relative humidity, temperature and mass of bed. Moisture removal capacity, moisture addition capacity and mass transfer coefficient are the parameter indices adopted to measure the heat and mass transfer characteristics of vertical packed and fluidized bed comprising clay-additives-CaCl2 composite desiccants. Comparing packed and fluidized beds, a higher surface area of bed in fluidization improves dehumidification performance and results in higher desorption rates. Experimental results confirmed that clay and clay-additives-based desiccants have desired adsorption–desorption characteristics of a suitable desiccant. The interesting advantage of fabricated clay and clay-additives-based composite adsorbents is that the air exits the desiccant bed at a lower temperature, saving cooling energy requirements of sorption-based systems. © 2022, The Author(s), under exclusive licence to The Brazilian Society of Mechanical Sciences and Engineering.
Analytical solution for free vibration of symmetric Terfenol-D layered functionally graded beam with different boundary conditions
(Springer Science and Business Media Deutschland GmbH, 2023) Patil, M.A.; Kadoli, R.
A unified analytical approach is established to predict the frequency behaviour of symmetric functionally layer-wise graded beams with an integrated Terfenol-D layer under simply supported, clamped-clamped, and clamped-simply supported boundary conditions. In contrast to previous research, the analytical solution relies on transcendental equations. Terfenol-D layered functionally graded beam uses Reddy’s generalised beam theory as the basis for its governing equation. First-order shear deformation and rotating inertia were taken into consideration in the study. To ensure the accuracy of the analytical solution, comparisons are made with the current differential quadrature solution based on Euler–Bernoulli beam theory. The current analytical solution yields frequency results that are in good agreement with those obtained by the differential quadrature approach. The present analytical means is straightforward and easy to understand as compared to previous researcher’s work. © 2023, The Author(s), under exclusive licence to The Brazilian Society of Mechanical Sciences and Engineering.
Bending and vibration studies of FG porous sandwich beam with viscoelastic boundary conditions: FE approach
(Taylor and Francis Ltd., 2023) Patil, R.; Joladarashi, S.; Kadoli, R.
Bending and vibration characteristics of FG porous sandwich beam with viscoelastic boundary conditions are investigated. Complex shear modulus and associated loss factor are considered for the viscoelastic interlayer. The beam is constrained by viscoelastic supports (VES) at either end. Complex stiffness model is adopted for VES. The transverse deflection, natural frequency, loss factors, and mode shapes are obtained by varying VES stiffness. Furthermore, the study is extended to sandwich beams with various (H, O, V, and X) porosity patterns. The results convey that VES contribution in vibration damping is more predominant when the supports are less stiff (more viscous). © 2022 Taylor & Francis Group, LLC.
Bifurcation buckling of isotropic annular disc using conforming and non-conforming finite element
(Elsevier Ltd, 2022) Kumar, A.; Kadoli, R.; Joladarashi, S.
Non-conforming and conforming polynomial is used to develop sector finite element for analysing the isothermal bifurcation buckling of isotropic annular disc. The sector finite element has three degrees of freedom for non-conforming and four degrees of freedom for conforming element respectively. To obtain the shape function for the sector finite element, the displacement polynomial is chosen from the Pascal's triangle, the displacement polynomial is used to obtain the polynomial corresponding to the nodal degree of freedom for the element and evaluated at each node of the sector finite element using the nodal coordinates. The kinematics, strain displacement relations and the stress strain relations is based on the Kirchhoff's plate theory. The stiffness matrix and geometric stiffness matrix are evaluated in MATHEMATICA and then imported in the FORTRAN complier. A FORTRAN CODE is developed to solve the eigenvalue problem for bifurcation buckling of clamped-clamped isotropic annular disc with uniform temperature rise. ORIGIN software is used to plot the buckled mode shape for non-conforming and conforming sector finite element for isotropic annular disc. The number of circumferential waves at the onset of bifurcation buckling increase as the radius ratio increases. The critical buckling temperature increases with increase in thickness of the annular disc, so is the case when the inner radius increases for a given outer radius and thickness of the annular disc. Â© 2022
Comparative analysis of steady state heat transfer in a TBC and functionally graded air cooled gas turbine blade
(2010) Coomar, N.; Kadoli, R.
Internal cooling passages and thermal barrier coatings (TBCs) are presently used to control metal temperatures in gas turbine blades. Functionally graded materials (FGMs), which are typically mixtures of ceramic and metal, have been proposed for use in turbine blades because they possess smooth property gradients thereby rendering them more durable under thermal loads. In the present work, a functionally graded model of an air-cooled turbine blade with airfoil geometry conforming to the NACA0012 is developed which is then used in a finite element algorithm to obtain a non-linear steady state solution to the heat equation for the blade under convection and radiation boundary conditions. The effects of external gas temperature, coolant temperature, surface emissivity changes and different average ceramic/metal content of the blade on the temperature distributions are examined. Simulations are also carried out to compare cooling effectiveness of functionally graded blades with that of blades having TBC. The results highlight the effect of including radiation in the simulation and also indicate that external gas temperature influences the blade heat transfer more strongly. It is also seen that graded blades with about 70% ceramic content can deliver better cooling effectiveness than conventional blades with TBC. © 2010 Indian Academy of Sciences.
Computational design of mould sprue for injection moulding thermoplastics
(Society for Computational Design and Engineering info@idsociety.org, 2016) Lakkanna, M.; Mohan Kumar, G.C.; Kadoli, R.
To injection mould polymers, designing mould is a key task involving several critical decisions with direct implications to yield quality, productivity and frugality. One prominent decision among them is specifying sprue-bush conduit expansion as it significantly influences overall injection moulding; abstruseness anguish in its design criteria deceives direct determination. Intuitively designers decide it wisely and then exasperate by optimising or manipulating processing parameters. To overwhelm that anomaly this research aims at proposing an ideal design criteria holistically for all polymeric materials also tend as a functional assessment metric towards perfection i.e., criteria to specify sprue conduit size before mould development. Accordingly, a priori analytical criterion was deduced quantitatively as expansion ratio from ubiquitous empirical relationships specifically a.k.a an exclusive expansion angle imperatively configured for injectant properties. Its computational intelligence advantage was leveraged to augment functionality of perfectly injecting into an impression gap, while synchronising both injector capacity and desired moulding features. For comprehensiveness, it was continuously sensitised over infinite scale as an explicit factor dependent on in-situ spatio-temporal injectant state perplexity with discrete slope and altitude for each polymeric character. In which congregant ranges of apparent viscosity and shear thinning index were conceived to characteristically assort most thermoplastics. Thereon results accorded aggressive conduit expansion widening for viscous incrust, while a very aggressive narrowing for shear thinning encrust; among them apparent viscosity had relative dominance. This important rationale would certainly form a priori design basis as well diagnose filling issues causing several defects. Like this the proposed generic design criteria, being simple would immensely benefit mould designers besides serve as an inexpensive preventive cliché to moulders. Its adaption ease to practice manifests a hope of injection moulding extremely alluring polymers. Therefore, we concluded that appreciating injectant?s polymeric character to design exclusive sprue bush offers a definite a priori advantage. © 2015 Society of CAD/CAM Engineers
Criticality of appreciating non-newtonianivity in plastic injection mould conduit design
(Begell House Inc., 2015) Lakkanna, M.; Kadoli, R.; Kumar, G.C.M.
The prime intention of this research was to emphasise criticality of Non-Newtonian injectant behaviour to design ideal runner conduits for plastic injection moulds. Power-law constitutive relation was representatively adopted so shear thinning index could contrast, both Non-Newtonian and Newtonian behaviours together. An a priori analytical solution was developed from Power-law constitutive relation analogous to celebrated Hagen-Poiseuille solution for tubular runner conduits. This solution leveraged the computational intelligence advantage to enable a design criteria for perfect injection into impression gap synchronising injector capacity, injectant character as well as desired moulding features. The proposed design criteria readily adapts in practise including extremely complicated feed system configurations. Further to incorporate comprehensiveness, continuous sensitivity method was also adopted to discriminate cruciality over an infinite dimension scale, which lead insight into various important aspects that would certainly form a basis to diagnose filling issues reasoning several defects. For representation a sample set of runners from realistic, productive moulds that were initially designed with Newtonian hypothesis and later during trails heuristically optimised were compared, interestingly, they were statistically skewed towards runner sizes that were directly determined appreciating Non-Newtonian injection behaviour. Therefore, it was concluded that Non-Newtonian injection behaviour should have significant prominence in injection mould design criteria. © 2015 Begell House, Inc.
Design and study of magnetization characteristics of a magnetostrictive (Tb0.3Dy0.7Fe1.95) actuator under zero pre-stress conditions for direct current input
(2013) Joshi, R.; Kadoli, R.
This paper presents the design of actuator using magnetostrictive material under zero prestress conditions for direct current input, which is being developed to move friction pads of a disc brake for braking action. Comparison of analytical, experiment and Maxwell simulation of coils in free air is being carried out to predict the magnetic field generated by them and magneto motive force reaching the measuring end of magnetostrictive material. Experiments are being conducted to verify the performance of magnetostrictive actuator for dc input under zero-preload conditions. A set of magnetization curves are being predicted using Jiles-Atherton model in the context of control applications that require an accurate characterization of the relation between input applied magnetic field and strain output by the actuator. Further the validation of Jiles-Atherton model results is being done with the results obtained from experiments. � (2013) Trans Tech Publications, Switzerland.
Design and study of magnetization characteristics of a magnetostrictive (Tb0.3Dy0.7Fe1.95) actuator under zero pre-stress conditions for direct current input
(2013) Joshi, R.; Kadoli, R.
This paper presents the design of actuator using magnetostrictive material under zero prestress conditions for direct current input, which is being developed to move friction pads of a disc brake for braking action. Comparison of analytical, experiment and Maxwell simulation of coils in free air is being carried out to predict the magnetic field generated by them and magneto motive force reaching the measuring end of magnetostrictive material. Experiments are being conducted to verify the performance of magnetostrictive actuator for dc input under zero-preload conditions. A set of magnetization curves are being predicted using Jiles-Atherton model in the context of control applications that require an accurate characterization of the relation between input applied magnetic field and strain output by the actuator. Further the validation of Jiles-Atherton model results is being done with the results obtained from experiments. Â© (2013) Trans Tech Publications, Switzerland.
Design of sprue bush for a plastic injection mould: A machine perspective
(2013) Lakkanna, M.; Kadoli, R.; Mohankumar, G.C.
Design methodology and criteria to configure sprue bush for enhancing functionality is systematically compiled from plastic injection moulding machine perspective. Sprue conduit's sensitivity to moulding objectives are quantitatively ghettoised as expansion ratio on the basis of ubiquitous empirical relationships. This generic, simple, inexpensive preventive criterion enables sprue bush conduit geometry design to exemplifying the melt injection specifically for a particular machine. Continuous Sensitivity Equation Method (CSEM) was adopted to sensitise sprue conduit expansion over infinite dimensional range exclusively for injection rate, maximum injection pressure and barrel size. Inferred results were exponential in nature with injection rate having direct proportionality, while maximum injection pressure and barrel size had inverse proportionality to conduit expansion off parting plane. Off them injection rate was found to be relatively more influential than injection pressure and barrel size.
Design of sprue bush for a plastic injection mould: A machine perspective
(Association for Machines and Mechanisms, 2013) Lakkanna, M.; Kadoli, R.; Mohan Kumar, G.C.
Design methodology and criteria to configure sprue bush for enhancing functionality is systematically compiled from plastic injection moulding machine perspective. Sprue conduit's sensitivity to moulding objectives are quantitatively ghettoised as expansion ratio on the basis of ubiquitous empirical relationships. This generic, simple, inexpensive preventive criterion enables sprue bush conduit geometry design to exemplifying the melt injection specifically for a particular machine. Continuous Sensitivity Equation Method (CSEM) was adopted to sensitise sprue conduit expansion over infinite dimensional range exclusively for injection rate, maximum injection pressure and barrel size. Inferred results were exponential in nature with injection rate having direct proportionality, while maximum injection pressure and barrel size had inverse proportionality to conduit expansion off parting plane. Off them injection rate was found to be relatively more influential than injection pressure and barrel size.
Developing partially oxidized NiCr coatings using the combined flame spray and plasma spray process for improved wear behaviour at high temperature
(Elsevier Ltd, 2021) Medabalimi, S.R.; Ramesh, M.R.; Kadoli, R.
The powders of NiCrBSiFe and NiCr are partially oxidized using a flame spray process and are deposited on MDN321 steel substrate using a plasma spray process. The effect of partial oxidization on microstructure, microhardness, density, bond strength, and porosity of the coatings is analyzed. The friction and wear behaviour of the coatings was assessed using a pin-on-disc tribometer by varying loads (10, 20 and 30 N), sliding velocities (1, 2 m/s) and temperatures (RT, 200, 400 and 600 °C). Worn surfaces of NiCrBSiFe and NiCr coatings consist of oxide phases of SiO2, NiO, Cr2O3 and NiCr2O4 at elevated temperatures. These phases contributed to reducing the wear rate by five folds in coated steels compared to uncoated steels at 600 °C. The wear rate in coating decreases with an increase in temperature. The coefficient of friction was reduced gradually with the temperature in coatings and substrate. The wear rate coefficient of NiCr coating was 1.7 times higher than the NiCrBSiFe coating. © 2021 Elsevier B.V.
Development of psychoacoustics index for motorcycle exhaust noise by multiple regression method
(Elsevier Ltd, 2023) Anas, D.; Joladarashi, S.; Kadoli, R.; Chavan, P.; Bhangale, R.
Exhaust sound is an essential characteristic of a motorcycle when it comes to the interest of young motorcycle riders. It has become such an essential characteristic that riders, after looking into the performance, style, and ergonomics, look into the exhaust sound produced by the muffler. It has thus become critical for motorcycle manufacturers to tune their mufflers in such a way that they are appealing to the customers while adhering to sound emission regulations. As per the current trend of Indian motorcycle rider's scenario, more attention is given to sound attributes like beat feeling, sportiness, and pleasantness. This research paper aims to develop a psychoacoustic model that can rate the exhaust sound of motorcycles targeting the Indian customer's preferences and interests with regard to the engine exhaust sound. Presently, a study has been carried out on beat feeling, sportiness, and pleasantness, a perceivable attribute of sound in the family of motorcycles. Motorcycle buyers often perceive the exhaust sound of motorcycles in idling conditions at some distance away from the muffler, which formed the basis while recording exhaust sounds. Initially, exhaust sounds were recorded, which led to the calculation of psychometrics as objective variables. The calculated objective variables were given as input to the multiple regression model. A jury panel consisting of experienced NVH professionals and riders evaluated these sounds on a 7-point evaluation scale. These subjective ratings were given as the target variable to the multiple regression model. The obtained model was later validated with subjective data of motorcycles, including those at the prototype stage. Thus, a model has been established to aid exhaust designers in comparing their motorcycle at different prototype stages with the competitor's vehicle, allowing them to make an early decision with respect to the muffler design modifications, thereby reducing the time-consuming and expensive jury tests. Â© 2022
Differential quadrature solution for vibration control of functionally graded beams with Terfenol-D layer
(Elsevier Inc. usjcs@elsevier.com, 2020) Patil, M.A.; Kadoli, R.
The governing differential equation of motion for vibration control of a functionally graded material (FGM) beam using magnetostrictive layers is solved using differential quadrature method(DQM). It is known that, when differential quadrature is implemented directly for the solution of governing differential equation for vibration control of beam, it is required to convert the generalised eigenvalue problem into standard eigenvalue problem. However in the present work, the original differential equation of vibration control of beam is be separated into two simpler second and fourth order differential equations using the separation of variables in conjunction with the characteristics equation of damped single degree of freedom system. Solution of corresponding two simpler differential equation also yields damped natural frequency and damped factor comparable to that of the former approach. It is to be noted that using either of the solutions using differential quadrature method ? point description of the physical domain at boundary is used to obtained the differential quadrature equations for the various boundary conditions of the beam. In order to assure the accuracy of formulation and solution using DQM, convergence behavior of natural frequencies is examined for five combinations of boundary conditions and comparison studies from the two solution approaches is presented. The effect of the location of the magnetostrictive layers, material properties and control parameters on the vibration suppression are investigated. © 2020 Elsevier Inc.
Differential-integral quadrature numerical solution for free and forced vibration of bidirectional functionally graded Terfenol-D curved beam
(Taylor and Francis Ltd., 2024) Patil, M.A.; Kadoli, R.; Saraf, S.; Naskar, S.
The dynamic behaviour of a bidirectional functionally graded Terfenol-D curved beam under a moving load is the focus of this study. Combined differential and integral quadrature solve the curved beam boundary value problem. A bidirectional functionally graded Terfenol-D curved beam's damping, damped frequencies for different boundary conditions, and mode shapes were examined in free vibration investigations. Based on accessible literature data, the findings are reliable. Furthermore, DQ-IQ numerical technique findings examine the impact of many factors, including control gain, thickness, moving load velocity, bidirectional gradation index, and multi-moving load. © 2023 Taylor & Francis Group, LLC.
Dry Sliding Wear Behavior of Super Duplex Stainless Steel AISI 2507: A Statistical Approach
(De Gruyter Open Ltd peter.golla@degruyter.com, 2016) Davanageri, M.; Narendranath, S.; Kadoli, R.
The dry sliding wear behavior of heat-treated super duplex stainless steel AISI 2507 was examined by taking pin-on-disc type of wear-test rig. Independent parameters, namely applied load, sliding distance, and sliding speed, influence mainly the wear rate of super duplex stainless steel. The said material was heat treated to a temperature of 850°C for 1 hour followed by water quenching. The heat treatment was carried out to precipitate the secondary sigma phase formation. Experiments were conducted to study the influence of independent parameters set at three factor levels using the L27 orthogonal array of the Taguchi experimental design on the wear rate. Statistical significance of both individual and combined factor effects was determined for specific wear rate. Surface plots were drawn to explain the behavior of independent variables on the measured wear rate. Statistically, the models were validated using the analysis of variance test. Multiple non-linear regression equations were derived for wear rate expressed as non-linear functions of independent variables. Further, the prediction accuracy of the developed regression equation was tested with the actual experiments. The independent parameters responsible for the desired minimum wear rate were determined by using the desirability function approach. The worn-out surface characteristics obtained for the minimum wear rate was examined using the scanning electron microscope. The desired smooth surface was obtained for the determined optimal condition by desirability function approach. © 2016 M. Davanageri et al., published by De Gruyter Open 2016.
Effect of boundary conditions and convection on thermally induced motion of beams subjected to internal heating
(2007) Malik, P.; Kadoli, R.; Ganesan, N.
Numerical exercises are presented on the thermally induced motion of internally heated beams under various heat transfer and structural boundary conditions. The dynamic displacement and dynamic thermal moment of the beam are analyzed taking into consideration that the temperature gradient is independent as well as dependent on the beam displacement. The effect of length to thickness ratio of the beam on the thermally induced vibration is also investigated. The type of boundary conditions has its influence on the magnitude of dynamic displacement and dynamic thermal moment. A sustained thermally induced motion is observed with progress of time when the temperature gradient being evaluated is dependent on the forced convection generated due to beam motion. A finite element method (FEM) is used to solve the structural equation of motion as well as the heat transfer equation. © Springer-Verlag 2007.